Phenylphosphinic Acid Research Articles

Synthesis of functionalized phenylphosphinic acid resins through Michael reaction and their ion-exchange properties

Novel, functional resins, containing variously substituted phenylphosphinic acid ligands, have been obtained via the Michael reaction. Reaction has been carried out on phenylphosphinic acid resin crosslinked with 2 wt.% of divinylbenzene using the following electrophiles: methyl chloroformate, ethyl bromoacetate, ethyl 2-bromopropionate, ethyl acrylate, ethyl methacrylate, acrylonitrile and methacrylonitrile giving the desired products with 60–97% yield. Resulting resins, having carboxylic acid function in α, β and γ position in respect to the phosphinic group have been used in ion-exchange/coordination of Cu(II), Cd(II), Ni(II), Zn(II) and Eu(III) from nitric acid solutions. It has been found that resins with carboxyl groups in α and β positions display higher divalent metal uptake, when the pH of the solution is above 1.5 and ion exchange is a prevailing process. Resins with either carboxyl or nitrile group in the γ position are less effective in metal ion uptake than the parent, phenylphosphinic polymer. In experiments with Eu(III) uptake from 0.1–1.0 M nitric acid solutions, where resins are supposed to operate mostly through coordination, none of synthesized resins performs better than the phenylphosphinic one. This means that introduction of carboxyl group to the phenylphosphinic acid ligand does not give a synergistic effect in coordination of metal ions.

Derivative of cyclen with three methylene(phenyl)phosphinic acid pendant arms. Synthesis and crystal structures of its lanthanide complexes

A new macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraylmethyltrimethylenetris(phenylphosphinic acid) H3L1 was synthesised and its complexes with lanthanides were prepared. X-Ray analysis of seven Ln complexes (Ln = La, Ce, Nd, Eu, Tb, Er, Yb) shows a formation of dimers [LnL1]2 with phosphinic acid bridges in the solid state. All complexes are isostructural and the coordination polyhedra are formed by four N atoms and four O atoms of phosphinic acid groups. A water molecule is placed near the O4 base. The LnOw distance is strongly dependent on Ln(III), it varies from 2.815(6) A in the La complex to 4.448(10) A in the Yb complex. The 31P NMR studies show formation of a rather complex mixture of isomers in solution. The dimer stability in solution is verified by reaction with triphenylphosphine oxide (tppo) and with pyridine N-oxide and by cyclic voltammetry.

Kinetics of Oxidation of Phosphinic, Phenylphosphinic and Phosphorous Acid by Benzyltrimethylammonium Chlorobromate

The oxidation of lower phosphorus oxyacids by benzyltrimethylammonium chlorobromate (BTMACB) proceeds by a mechanism involving a hydride-ion transfer from oxyacids to the oxidant in the rate-determining step.

Kinetics and mechanism of the oxidation of lower oxyacids of phosphorus by hexamethylenetetramine bromine

The oxidation of lower oxyacids of phosphorus by hexamethylenetetramine bromine (HABR) in glacial acetic acid resulted in the formation of corresponding oxyacids with phosphorus in a higher oxidation state. The reaction exhibited 2:1 stoichiometry. The reaction is first order with respect to HABR. Michaelis–Menten-type kinetics were observed with respect to the acids. The formation constant of the phenylphosphinic acid–HABR complex also has been determined spectrophotometrically. The thermodynamic parameters for the complex formation and the activation parameters for their decomposition were calculated. The reaction showed the presence of a substantial kinetic isotope effect. It is proposed that the HABR itself is the reactive oxidizing species. It has been shown that the pentacoordinated tautomer of the phosphorus oxyacid is the reactive reductant. A suitable mechanism has been proposed. © 2000 John Wiley & Sons, Inc. Int J Chem Kinet 32: 165–170, 2000

Fluorescence and cofluorescence enhancement of Tb3+ and Eu3+ using phenyl phosphonic and phenyl phosphinic acids as ligands

Fluorescence enhancement of Tb3+ and Eu3+ in aqueous solution has been studied using phenyl phosphonic acid (PPOA), C6H5P (O)(OH) 2 and phenyl phosphinic acid (PPIA), C6H5P (O)(OH) H as ligands. The enhancement, a result of ligand sensitized fluorescence, was observed to be more than two orders of magnitude with these ligands. On addition of trioctyl phosphine oxide (TOPO), a synergistic ligand, Tb3+ and Eu3+ fluorescence were further enhanced in PPIA acid complexes. The Tb3+ and Eu3+ fluorescence in their PPOA complexes were enhanced by over two orders of magnitude, by the addition of La3+; a process known as cofluorescence. The present study demonstrates for the first time cofluorescence in phosphonic ligands. While synergism due to TOPO was observed with PPIA, cofluorescence was observed with PPOA.

Experimental and Quantum Chemical Studies of 2-Phosphinylphenol Derivatives

Carbon-oxygen bonds ortho to a phosphoryl group in triarylphosphine oxides undergo cleavage when the oxides are either fused with potassium hydroxide or treated with potassium tert-butoxide in refluxing toluene, presumably through a nucleophilic addition-elimination mechanism. Thus, bis(2-hydroxyphenyl)phenylphosphine oxide is produced along with the expected 2-phenoxyphenyl(phenyl)phosphinic acid from 10-phenyl-10H-phenoxaphosphine 10-oxide. The latter starting material is also produced, together with bis(2-hydroxyphenyl)phenylphosphine oxide, when bis(2-methoxyphenyl)phenylphosphine oxide is fused with potassium hydroxide. Fusion of bis(2-methoxyphenyl)phenylphosphine oxide with sodium hydroxide, however, yields 2-hydroxyphenyl(phenyl)phosphinic acid. Ab initio quantum chemical studies confirm that the downfield 31P chemical shift that is observed in 2-phosphinylphenols is due to hydrogen bonding to the phosphoryl group.

Synthesis, crystal structures and NMR and luminescence spectra of lanthanide complexes of 1,4,7,10-tetraazacyclododecane with N-methylene(phenyl)phosphinic acid pendant arms †

Complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayltetramethylenetetrakis(phenylphosphinic acid) H4L1 with yttrium and a number of lanthanides were synthesized and the crystal structures of Li[LaL1(H2O)]·10H2O and Li[CeL1(H2O)]·10H2O determined. The complexes are isostructural with RSRS configurations at the phosphorus atoms. The ligand is co-ordinated by four nitrogen atoms in a plane and by four phosphinate oxygen atoms in a parallel plane. The planes form a twisted square prismatic co-ordination sphere. A molecule of water capping the O4 plane completes the co-ordination sphere of both ions. Solution properties of the complexes were investigated by 1H and 31P NMR. In solution six possible isomers with different configurations on phosphorus atoms are in equilibrium. The most abundant shows the RRRS configuration. A dynamic behavior similar to lanthanide complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid is not observed. The NMR as well as luminescence measurements show that no water molecule is co-ordinated directly to the lanthanide ions in solution. The ions Li+and Na+ form stable ion pairs with the complexes in methanol-d4 solution as confirmed by the lanthanide induced shift of 7Li and 23Na resonances in the presence of paramagnetic lanthanide ions. The ion pairs are not stable in aqueous solution. The alkali metal ion is located close to fourfold magnetic axes of the complexes above the oxygen atoms and between the phenyl rings. Luminescence spectra of [LnL1]–, Ln = Eu or Tb, indicate low symmetry of the species and co-ordination number 8.

Solvent Extraction of Lanthanide(III) with 1,3-Benzenedimethylbis(phenylphosphinic acid)

Solvent Extraction of Lanthanide(III) with 1,3-Benzenedimethylbis(phenylphosphinic acid)

Crystal structure of cis-1,3-bis(phenylphosphinic acid)-2-oxapropane, [PhP(=O)(OH)CH2]2O

Article Crystal structure of cis-1,3-bis(phenylphosphinic acid)-2-oxapropane, [PhP(=O)(OH)CH2]2O was published on December 1, 1997 in the journal Zeitschrift für Kristallographie - New Crystal Structures (volume 212, issue 1).

ChemInform Abstract: Facile Synthesis of Functionalized Phenylphosphinic Acid Derivatives.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Facile synthesis of functionalised phenylphosphinic acid derivatives

Functionalised phenylphosphinic acid derivatives have been synthesised by addition of bis(trimethylsilyl)phenylphosphonite 2 to a series of electrophiles.

Addition reactions of compounds with the P(:O)H group to fluorinated ketimines

N, N′-Disubstituted derivatives of 5,6-benzo-2 H-2-oxo-1,3,2-diazaphosphorinan-4-one ( 2–6), 1,3,5-trimethyl-2 H-2-oxo-1,3,5-triaza-2 λ 4-phosphorinan-4,6-dione ( 12), phenylphosphinic acid ( 14) and dimethylphosphine oxide ( 16) have been added across the CN double bond of phenyltrifluoromethylketimine ( 1) in the presence of catalytic quantities of triethylamine, leading to the formation of N, N′-disubstituted derivatives of 5,6-benzo-2-(1-amino-1-phenyl-2,2,2-trifluoroethyl)-2-oxo-1,3,2-diazaphosphorinan-4-one ( 7–11), 2-(1-amino-1-phenyl-2,2,2-trifluoroethyl)-1,3,5-trimethyl-2-oxo-1,3,5-triaza-2λ 4-phosphorinan-4,6-dione ( 13), phenyl-(1-amino-1-phenyl-2,2,2-trifluoroethyl)phosphinic acid ( 15) and dimethyl-(1-amino-1-phenyl-2,2,2-trifluoroethyl) phosphine oxide ( 17), respectively. Addition of N, N′-disubstituted derivatives of 5,6-benzo-2 H-2-oxo-1,3,2-diazaphosphorinan-4-one ( 2–4) and ( 21) and of 1,3,5-trimethyl-2 H-2-oxo-1,3,5-triaza-2 λ 4-phosphorinan-4,6-dione ( 12) across the CN double bond of bis(trifluoromethyl)ketimine ( 20) resulted in N, N′-disubstituted derivatives of 5,6-benzo-2-(1-amino-1-trifluoromethyl-2,2,2-trifluoroethyl)-2-oxo-1,3,2-diphosphorinan-4-one ( 22–25) and 2-(1-amino-1-trifluoromethyl-2,2,2-trifluoroethyl)-1,3,5-trimethyl-2-oxo-1,3,5-triaza-2λ 4-phosphorinan-4,6-dione ( 26), respectively. The compounds were characterised by 1H, 13C, 19F and 31P NMR spectroscopy, mass spectrometry, elemental analysis and a single-crystal X-ray structure analysis in the case of compound 22. The heterocycle displays an envelope conformation. The structure shows one intermolecular hydrogen bond, leading to the formation of centrosymmetric dimers.

Synthesis and properties of tetra-μ-acetatodiruthenium(II,III) phenylphosphinate and phenylphosphonate complexes: X-ray crystal structures of [Ru 2(μ-O 2CCH 3) 4(HPhPO 2) 2]H and [Ru 2(μ-O 2CCH 3) 4(PhPO 3H) 2]H·H 2O

Phenylphosphinic acid (HPhPO 2H) and phenylphosphonic acid (PhPO 3H 2) react with a methanolic solution of [Ru 2(μ-O 2CCH 3) 4(O 2CCH 3) 2]H·0.7H 2O at room temperature to give [Ru 2(μ-O 2CCH 3) 4(HPhPO 2) 2H ( 1) and [Ru 2(μ-O 2CCH 3) 4 (PhPO 3H) 2]H·H 2O ( 2), respectively. The X-ray crystal structures of 1 and 2 each show the RuRu core to be ligated by four bridging bidentate acetate ligands [RuRu distances: 1 = 2.272(1) Å; 2 = 2.267(2) Å] and two axial phenylphosphinate and phenylphosphonate ligands, respectively. In each complex the individual bimetallic molecules are linked together by a hydrogen ion which bridges the oxygen atoms of neighbouring axial ligands. In 2 the water molecule is also hydrogen-bonded to one of the axial phenylphosphonate groups. Spectroscopic, magnetic and cyclic voltammetric data for the complexes are given.

Effect of some phosphorous compounds on the thermo‐oxidative stability of poly(ethylene terephthalate)

AbstractA series of poly(ethylene terephthalate) (PET) samples was prepared from dimethyl terephthalate and ethylene glycol. In each sample a phosphorous compound was added as heat stabilizer after the transesterification and before the polycondensation. These compounds were: phosphoric acid, tributyl phosphate, triphenyl phosphate, phenyl‐phosphonic acid, phenylphosphinic acid, and sodium phenylphosphinate. Firstly, their interference with the transesterification catalyst was examined. Their stabilization effect was estimated by DSC analysis in nitrogen and air. Various thermal criteria have been used, such as stabilization coefficient and induction period of oxidation. Under the conditions used for polymerization, the more efficient stabilizers were tributyl phosphate, phenylphosphonic and phenylphosphinic acid.

Synthesis and Anomalous Reactivity of 5-Bromo-3,5- Di-t-Butyl-2-Phenyl-1,2-Oxaphosphol-3-Ene 2-Oxide and its 4-Bromo Analog

Abstract Reaction of 2,2,6,6-tetramethyl-4-heptyn-3-0l with dichlorophenylphosphine leads to 2,2,6,6-tetramethyl-3,4-heptadien-3-1 phenyl phosphinic acid (11, which undergoes Ag+-catalyzed cyclization to 3,5-di-t-butyl-2-phenyl-1,2-oxaphosphol-3-ene 2-oxide (2H, 75-55% z, 25–45% E). Electrophilic bromination of 1 affords 2Br, the 4-bromo derivative of 2H, as a 75% Z, 25% E diastereomer mixture from which pure (Z)-2Br can be isolated.

Reactions of 1,2-oxaphospholenes. 7. Anomalous low reactivity of a tertiary allylic bromide. The crystal and molecular structure of (E)-4,5-dibromo-3,5-di-tert-butyl-2-phenyl-1,2-oxaphosphol-3-ene 2-oxide

Reaction of 2,2,6,6-tetramethgl-4-heptyn-9-ol (5) with dichlorophenylphosphine leads to (2,2,6,-tetramethyl-3,4 heptadien-3-yl)phenylphosphinic acid (7), which undergoes Ag + -catalysed cyclization to 3,5-di-tert- butyl-2-phenyl-1,2-oxaphosphol-3-ene 2-oxide (1e, 75-55% Z, 25-45%E). Electrophilic bromination of 7 affords 1f, the 4-bromo derivative of 1e, as a 75% Z 55% E diastereomer mixture from which pure (Z)-1f can be isolated. Free radical allylic bromination of 1e and 1f leads to the corresponding 5-bromo derivatives 2e and 2f, each as the single diastereoisomer

Facile oxidation of phenylphosphinic acid to phenylphosphonic acid using [Cu 2(μ-O 2CCH 3) 4(H 2O) 2]: X-ray crystal structures of monomeric [Cu(PhPO 3H) 2(C 5H 5N) 4]·2CH 3OH and [Cu(PhPO 3H) 2(C 5H 5N) 4

Phenylphosphinic acid (HPhPO 2H) is oxidized to phenylphosphonic acid (PhPO 3H 2) at room temperature using a solution of [Cu 2(μ-O 2CCH 3) 4(H 2O) 2] in pyridine. The phenylphosphonic acid was recovered as the monomeric copper(II) complex [Cu(PhPO 3H) 2(C 5H 5N) 4]·H 2O ( 1a), and the reaction thought to proceed via a copper(I) intermediate. Recrystallization of 1a from methanol gave [Cu(PhPO 3H) 2(C 5H 5N) 4]·2CH 3OH ( 1b). The unsolvated complex [Cu(PhPO 3H) 2(C 5H 5N) 4] ( 1c) was prepared by refluxing polymeric [Cu(PhPO 3)(H 2O)] ( 2) in pyridine. The X-ray crystal structures of 1b and 1c show that in each of these monomeric complexes the copper(II) ion is ligated by four equatorial pyridine molecules and two axial monoanionic phenylphosphonate groups. A cyclic voltammetric study of 1a revealed a quasi-reversible Cu 2+/Cu + couple with E 1/2 = +228 mV (vs Ag/AgCl).

Reaction of Alkyl Sulfoxides and Phenylphosphinic Acid with Amines. Alternative Reagents for Secondary Amines N-Alkylation

Abstract Phenylphosphinic acid and dialkylsulfoxides are found to be alternative reagents for respectively the reducing reagent (formic acid) and the alkylating reagent (aldehyde) currently used for secondary amines N-alkylation. Primary amines do not react with this system, but phenylglycine is decarboxilated to benzylamine.

Synthesis and structure of chiral metal complexes of polyazacycloalkane ligands incorporating phosphinic acid donors

The chiral copper(II) and gallium(III) complexes of a triazatris(phenylphosphinic acid) ligand have very similar structures: the anionic copper complex possesses C3 symmetry, shows no Jahn–Teller distortion at 293 K nor at 123 K and is resistant to protonation.

ChemInform Abstract: Kinetics and Mechanism of the Oxidation of Phosphinic, Phenylphosphinic, and Phosphorous Acids by Pyridinium Fluorotrioxochromate(VI)

Oxidation of the lower phosphorus oxyacids by [C5H5NH][CrO3F] results in the formation of corresponding oxyacids in the higher valence states. The reaction is first order with respect to the oxidant concentration. A Michaelis–Menten type kinetics was observed with respect to the substrate, indicating the formation of a complex in a pre-equilibrium. The formation constants and the rates of disproportionation of the complexes have been evaluated at different temperatures. The reaction exhibits a substantial primary kinetic isotope effect. The rates in 19 different organic solvents have been analysed using Kamlet-Taft and Swain equations. It has been found that the cation-solvating power of the solvents plays an important role. It is proposed that the ‘inactive’ tautomer of the phosphorus oxyacids is the reactive reductant, and that transfer of a hydride ion from the P–H bond to the oxidant in the rate-determining step occurs.